package com.zzj.filter;

import com.alibaba.fastjson.JSONObject;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.zzj.utils.JwtUtil;
import io.jsonwebtoken.Claims;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;

import org.springframework.cloud.gateway.filter.GlobalFilter;

import org.springframework.core.Ordered;
import org.springframework.http.HttpCookie;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

import java.util.HashMap;
import java.util.Map;


//@Component
public class AuthorizeFilter implements GlobalFilter, Ordered {

    //令牌头名字
    private static final String AUTHORIZE_TOKEN = "Authorization";

    /***
     *全局过滤器
     *@param exchange
     *@param chain
     *@return
     */
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain){

        //获取Request、Response对象
        ServerHttpRequest request = exchange.getRequest();
        ServerHttpResponse response = exchange.getResponse();

        //获取请求的URI
        String path = request.getURI().getPath();

        //如果是登录、goods等开放的微服务[这里的goods部分开放],则直接放行,这里不做完整演示，完整演示需要设计一套权限系统
        if (path.startsWith("/user/login")){
            //放行
            Mono<Void> filter = chain.filter(exchange);
            return filter;
        }

        //获取头文件中的令牌信息
        String tokent = request.getHeaders().getFirst(AUTHORIZE_TOKEN);

        //如果头文件中没有，则从请求参数中获取
        if (StringUtils.isEmpty(tokent)){
            tokent = request.getQueryParams().getFirst(AUTHORIZE_TOKEN);
        }
        //从Cookie中获取令牌数据
        HttpCookie first = request.getCookies().getFirst(AUTHORIZE_TOKEN);
        if (first!=null){
            tokent = first.getValue();
        }
        //如果为空，则输出错误代码
        if (StringUtils.isEmpty(tokent)){
            //设置方法不允许被访问，405错误代码
            response.setStatusCode(HttpStatus.METHOD_NOT_ALLOWED);
            return response.setComplete();
        }

        //解析令牌数据
        try {
            Claims claims = JwtUtil.parseJWT(tokent);
            //将令牌数据添加到头文件中
            request.mutate().header(AUTHORIZE_TOKEN,claims.toString());

            String sub=claims.getSubject();

            ObjectMapper mapper=new ObjectMapper();

            Map map = mapper.readValue(sub, Map.class);

            System.out.println(map);

            request.mutate().header("uid",map.get("uid").toString());
        } catch (Exception e){
            e.printStackTrace();
            //解析失败，响应401错误
            response.setStatusCode(HttpStatus.UNAUTHORIZED);
            return response.setComplete();
        }

        //放行
        return chain.filter(exchange);
    }


    /***
     *过滤器执行顺序
     *@return
     */
    @Override
    public int getOrder(){
        return 0;
    }
}
